Reefer pre-trip inspection

A reefer pre-trip inspection (PTI) is the functional test of a refrigerated container’s machinery before it is loaded for a voyage. The technician runs the unit through a controlled cool-down and, where capability allows, a full PTI that exercises compressor, evaporator and condenser fans, defrost, controller sensors, and the controlled or modified atmosphere system, logging the results. A passed PTI confirms the unit can hold the set point for perishable cargo such as fruit, meat, or pharmaceuticals. A unit that fails PTI is repaired or rejected before stuffing, since a mid-voyage failure on a non-monitored leg can spoil the entire load.